Materialize. Get access to autocomplete element properties

Question

I guess answer should be easy, but I´m going mad trying to find an answer.

Let´s say that I have a Materialize autocomplete element defined like this.

 $('#element_id).autocomplete({
                limit:5,
                data:{"a":null,"b":null,"c":null},
                onAutocomplete:function(){whatEverYouWannaDoAfterCompletion()}
            });

However, getting the selected value has no problem, my question is... Is it possible to get selected index with activeIndex autocomplete item property or should I "navigate" throught rendered component to find the selected ocurrence?.

Thank you.